It has been my experience that Dept's tend to keep them till ordered to return them. I know a guy that surrendered his firearm to an officer after he and his girlfriend had a verbal argument and her mom called the police. One of those he has a gun in the house but it was not involved in the incident and officer asks to see it then decides to hold onto it till tomorrow till everyone cools off. Tomorrow turns into I had to turn it in and my Sergeant has to give it back to you. That turned into you're probably not getting it back. Took a lawyer going to a judge and getting a court order to release the firearm to the owner.